1# Copyright 2021 The Pigweed Authors 2# 3# Licensed under the Apache License, Version 2.0 (the "License"); you may not 4# use this file except in compliance with the License. You may obtain a copy of 5# the License at 6# 7# https://www.apache.org/licenses/LICENSE-2.0 8# 9# Unless required by applicable law or agreed to in writing, software 10# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 11# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 12# License for the specific language governing permissions and limitations under 13# the License. 14"""Example text input-output Plugin.""" 15 16from typing import TYPE_CHECKING 17 18from prompt_toolkit.document import Document 19from prompt_toolkit.key_binding import KeyBindings, KeyPressEvent 20from prompt_toolkit.layout import Window 21from prompt_toolkit.widgets import SearchToolbar, TextArea 22 23from pw_console.widgets import ToolbarButton, WindowPane, WindowPaneToolbar 24 25if TYPE_CHECKING: 26 from pw_console.console_app import ConsoleApp 27 28 29class CalcPane(WindowPane): 30 """Example plugin that accepts text input and displays output. 31 32 This plugin is similar to the full-screen calculator example provided in 33 prompt_toolkit: 34 https://github.com/prompt-toolkit/python-prompt-toolkit/blob/3.0.23/examples/full-screen/calculator.py 35 36 It's a full window that can be moved around the user interface like other 37 Pigweed Console window panes. An input prompt is displayed on the bottom of 38 the window where the user can type in some math equation. When the enter key 39 is pressed the input is processed and the result shown in the top half of 40 the window. 41 42 Both input and output fields are prompt_toolkit TextArea objects which can 43 have their own options like syntax highlighting. 44 """ 45 46 def __init__(self): 47 # Call WindowPane.__init__ and set the title to 'Calculator' 48 super().__init__(pane_title='Calculator') 49 50 # Create a TextArea for the output-field 51 # TextArea is a prompt_toolkit widget that can display editable text in 52 # a buffer. See the prompt_toolkit docs for all possible options: 53 # https://python-prompt-toolkit.readthedocs.io/en/latest/pages/reference.html#prompt_toolkit.widgets.TextArea 54 self.output_field = TextArea( 55 # Optional Styles to apply to this TextArea 56 style='class:output-field', 57 # Initial text to put into the buffer. 58 text='Calculator Output', 59 # Allow this buffer to be in focus. This lets you drag select text 60 # contained inside, and edit the contents unless readonly. 61 focusable=True, 62 # Focus on mouse click. 63 focus_on_click=True, 64 ) 65 66 # This is the search toolbar and only appears if the user presses ctrl-r 67 # to do reverse history search (similar to bash or zsh). Its used by the 68 # input_field below. 69 self.search_field = SearchToolbar() 70 71 # Create a TextArea for the user input. 72 self.input_field = TextArea( 73 # The height is set to 1 line 74 height=1, 75 # Prompt string that appears before the cursor. 76 prompt='>>> ', 77 # Optional Styles to apply to this TextArea 78 style='class:input-field', 79 # We only allow one line input for this example but multiline is 80 # supported by prompt_toolkit. 81 multiline=False, 82 wrap_lines=False, 83 # Allow reverse history search 84 search_field=self.search_field, 85 # Allow this input to be focused. 86 focusable=True, 87 # Focus on mouse click. 88 focus_on_click=True, 89 ) 90 91 # The TextArea accept_handler function is called by prompt_toolkit (the 92 # UI) when the user presses enter. Here we override it to our own accept 93 # handler defined in this CalcPane class. 94 self.input_field.accept_handler = self.accept_input 95 96 # Create a toolbar for display at the bottom of this window. It will 97 # show the window title and toolbar buttons. 98 self.bottom_toolbar = WindowPaneToolbar(self) 99 self.bottom_toolbar.add_button( 100 ToolbarButton( 101 key='Enter', # Key binding for this function 102 description='Run Calculation', # Button name 103 # Function to run when clicked. 104 mouse_handler=self.run_calculation, 105 ) 106 ) 107 self.bottom_toolbar.add_button( 108 ToolbarButton( 109 key='Ctrl-c', # Key binding for this function 110 description='Copy Output', # Button name 111 # Function to run when clicked. 112 mouse_handler=self.copy_all_output, 113 ) 114 ) 115 116 # self.container is the root container that contains objects to be 117 # rendered in the UI, one on top of the other. 118 self.container = self._create_pane_container( 119 # Show the output_field on top 120 self.output_field, 121 # Draw a separator line with height=1 122 Window(height=1, char='─', style='class:line'), 123 # Show the input field just below that. 124 self.input_field, 125 # If ctrl-r reverse history is active, show the search box below the 126 # input_field. 127 self.search_field, 128 # Lastly, show the toolbar. 129 self.bottom_toolbar, 130 ) 131 132 def pw_console_init(self, app: 'ConsoleApp') -> None: 133 """Set the Pigweed Console application instance. 134 135 This function is called after the Pigweed Console starts up and allows 136 access to the user preferences. Prefs is required for creating new 137 user-remappable keybinds.""" 138 self.application = app 139 self.set_custom_keybinds() 140 141 def set_custom_keybinds(self) -> None: 142 # Fetch ConsoleApp preferences to load user keybindings 143 prefs = self.application.prefs 144 # Register a named keybind function that is user re-mappable 145 prefs.register_named_key_function( 146 'calc-pane.copy-selected-text', 147 # default bindings 148 ['c-c'], 149 ) 150 151 # For setting additional keybindings to the output_field. 152 key_bindings = KeyBindings() 153 154 # Map the 'calc-pane.copy-selected-text' function keybind to the 155 # _copy_all_output function below. This will set 156 @prefs.register_keybinding('calc-pane.copy-selected-text', key_bindings) 157 def _copy_all_output(_event: KeyPressEvent) -> None: 158 """Copy selected text from the output buffer.""" 159 self.copy_selected_output() 160 161 # Set the output_field controls key_bindings to the new bindings. 162 self.output_field.control.key_bindings = key_bindings 163 164 def run_calculation(self): 165 """Trigger the input_field's accept_handler. 166 167 This has the same effect as pressing enter in the input_field. 168 """ 169 self.input_field.buffer.validate_and_handle() 170 171 def accept_input(self, _buffer): 172 """Function run when the user presses enter in the input_field. 173 174 Takes a buffer argument that contains the user's input text. 175 """ 176 # Evaluate the user's calculator expression as Python and format the 177 # output result. 178 try: 179 output = "\n\nIn: {}\nOut: {}".format( 180 self.input_field.text, 181 # NOTE: Don't use 'eval' in real code (this is just an example) 182 eval(self.input_field.text), # pylint: disable=eval-used 183 ) 184 except BaseException as exception: # pylint: disable=broad-except 185 output = "\n\n{}".format(exception) 186 187 # Append the new output result to the existing output_field contents. 188 new_text = self.output_field.text + output 189 190 # Update the output_field with the new contents and move the 191 # cursor_position to the end. 192 self.output_field.buffer.document = Document( 193 text=new_text, cursor_position=len(new_text) 194 ) 195 196 def copy_selected_output(self): 197 """Copy highlighted text in the output_field to the system clipboard.""" 198 clipboard_data = self.output_field.buffer.copy_selection() 199 self.application.application.clipboard.set_data(clipboard_data) 200 201 def copy_all_output(self): 202 """Copy all text in the output_field to the system clipboard.""" 203 self.application.application.clipboard.set_text( 204 self.output_field.buffer.text 205 ) 206